package com.itheima.filter;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.annotation.WebInitParam;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/*
   解决Post提交中文乱码问题
 */
@WebFilter(value = "/*", initParams = {@WebInitParam(name = "encoding", value = "UTF-8")})
public class EncodingFilter implements Filter {
    private String encoding;

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        encoding = filterConfig.getInitParameter("encoding");
        System.out.println("encoding");
    }


    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        //对象转换
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;
        //设置请求和响应的字符集编码
        request.setCharacterEncoding(encoding);
        response.setContentType("text/html;charset=" + encoding);
        //放行
        filterChain.doFilter(request, response);
    }
}
